1. Field of the Invention
The present invention relates to a retractable handle for a locking device for a retractable handle of wheeled luggage and more particularly to such a locking device with improved characteristics.
2. Description of Related Art
Typically, a single locking device is provided in the retractable handle for controlling the handle in a retracted position and an extended position. That is, the retractable handle may be extended to a maximum length when towing on the ground by traveler as well as retracted into a minimum length (i.e., rested on the top of luggage) appropriate for stowage or transport. It is known that luggage equipped with a retractable handle is very popular among travelers. Thus many types of luggage with retractable handle are commercially available in which each type of luggage mounted with a unique locking device. For example, the single locking device comprises wedge members, springs, lock blocks (or pins), supporting members, detents, and connecting wires.
Various designs of locking devices have been found in a search as follows: U.S. Pat. No. 5,581,846 entitled xe2x80x9cControlling Handle Structure for Full Rods of a Luggagexe2x80x9d, and U.S. Pat. No. 5,628,088 entitled xe2x80x9cMultistage Adjustable Device for Trunk Bracketxe2x80x9d. As to the complex retractable handle with multiple retaining slots, various designs thereof also have been found in a search as follows: Taiwanese Patent Published No. 337,100 entitled xe2x80x9cImproved Retractable Handle of Luggagexe2x80x9d; No. 362,404 entitled xe2x80x9cActivation Mechanism for Retractable Handle with Multiple Retaining Slots of Luggagexe2x80x9d; and No. 368,815 entitled xe2x80x9cImproved Activation Mechanism for Retractable Handle with Multiple Retaining Slots of Luggagexe2x80x9d. But these are unsatisfactory for the purpose for which the invention is concerned for the following reasons:
1. Complex in structure.
2. Susceptible to breakdown.
3. Time consuming in assembly.
4. A horizontal component force is applied on the slope because connecting wires, detents, and wedges interact with one another when user presses on the push button to activate the locking mechanism through the connecting wires. This horizontal component force may control the activation of lock blocks (or pins) and detents. However, an undesirable gap still exists between a fully retracted handle and the bezel. This is a significant drawback.
5. A horizontal component force is applied on the slope when lock blocks (or pins) are activated by slanted guide groove. This causes additional drawbacks in addition to those described above. In detail, the ratio of extendible maximum length to retractable minimum length is significantly lowered due to the implementation of multiple-segment longitudinal slanted guide groove. This limits the effective length of extended handle. Further, it has the disadvantages of complex in structure, difficult to adjust the assembly, low yield of finished product, and higher manufacturing cost. Thus improvement is desirable.
It is therefore an object of the present invention to provide a locking device for handle assembly for significantly increasing the ratio of extendible maximum length to retractable minimum length of handle such that a predetermined extendible length is achievable.
It is another object of the present invention to provide a locking device for handle assembly wherein second locking device secures to the bottom of the second sliding tube. The second locking device has three members at most. Further, only a snapping is required to finish the assembly of second locking device and second sliding tube without any fastener. This second locking device has the advantages of simple in structure, quick assembly, and durable.
It is still another object of the present invention to provide a locking device for handle assembly wherein lock member of first locking device is provided at the bottom of first housing of the first locking device capable of directly moving into the lock hole of the second locking device so as to cause lock pin of the second locking device to become disengaged. There is no horizontal component force created on the slope as occurred in the prior art because the lock member of the first locking device directly inserts into the lock hole of second locking device as well as first locking device and second locking device are engaged in a planar surface. This ensures that there is no gap between the first and second locking devices such that the handle grip of the fully retracted handle may rest on the bezel.
To achieve the above and other objects, the present invention provides a locking device for handle assembly comprising: a first sliding tube; a first locking device detachably attached to the bottom of the first sliding tube; a second sliding tube for allowing the first sliding tube to slidingly move therein having a hole; a second locking device detachably attached to the bottom of the second sliding tube; a support tube for allowing the second sliding tube to slidingly move therein having a hole; and a first connecting means connected between a push button and the first locking device.
Whereby the handle is retracted when the push button is not pressed, the first sliding tube is received in the second sliding tube and the second sliding tube is received in the support tube, the projection of the first locking device is engaged with the lower hole of the second sliding tube, the bottom of the first locking device is biased against the top of the sliding block of the second locking device so as to move the lock member of the first locking device into the lock hole of the second locking device to cause the lock pin of the second locking device to retract into the support tube, whereby the handle is locked in a retracted position.
The push button is pressed. Then handle is pulled upward to cause the first locking device to move up so as to move the lock pin of the first locking means into lower hole of the second sliding tube. Grasp handle grip to pull first sliding tube upward for separating the lock member on the bottom of first locking device from lock hole of the second locking device. Then second locking device moves up as the second sliding tube and first sliding tube move up together until the second lock pin comes into contact with upper hole of the support tube and locks therein. Now handle is in a fully extended position for allowing luggage to be towed along the ground.